User device and method for operating sidelink communication

Abstract

A user equipment arranged to operate sidelink communication. The user equipment includes a transceiver that is configured to receive a first signal from a first synchronization source. The user equipment further includes a processor which is configured to obtain a set of sidelink synchronization signal (SLSS), identifiers (IDs). The processor is further configured to operate power control of transmission of a synchronization signal based on the first signal and the set of SLSS IDs. The user equipment manifests a reduced power consumption, an improved energy efficiency as well as an efficient synchronization coverage expansion, in and out of network coverage of a base station.

What is claimed is: 
     
         1 . A User Equipment, UE, ( 102 ) arranged to operate sidelink communication, the UE ( 102 ) comprising:
 a transceiver ( 104 ) being configured to receive a first signal from a first synchronization source ( 108 ), and   a processor ( 106 ) being configured to: obtain a set of sidelink synchronization signal, SLSS, identifiers, IDs; operate power control of transmission of a synchronization signal based on the first signal and the set of SLSS IDs.   
     
     
         2 . The UE ( 102 ) according to  claim 1 , wherein the processor ( 106 ) is further configured to:
 obtain the set of sidelink synchronization signal, SLSS, identifiers, IDs by receiving a set of SLSS IDs from a serving base station, BS ( 202 ).   
     
     
         3 . The UE ( 102 ) according to  claim 1 , wherein the processor ( 106 ) is further configured to:
 obtain the set of sidelink synchronization signal, SLSS, identifiers, IDs by receiving a set of SLSS IDs from a synchronization reference, SyncRef, UE ( 208 ,  210 ,  212 ,  214 ,  502 ).   
     
     
         4 . The UE ( 102 ) according to  claim 1 , wherein the processor ( 106 ) is further configured to:
 obtain the set of sidelink synchronization signal SLSS, identifiers, IDs by determining the set of SLSS IDs based on an SLSS ID of a synchronization reference, SyncRef, UE ( 208 ,  210 ,  212 ,  214 ,  502 ) and rules of pre-configuration.   
     
     
         5 . The UE ( 102 ) according to  claim 4 , wherein the set of SLSS IDs is determined to include the SLSS ID used by the synchronization reference, SyncRef, UE ( 208 ,  210 ,  212 ,  214 ,  502 ). 
     
     
         6 . The UE ( 102 ) according to  claim 5  further having a priority, wherein the processor ( 106 ) is further configured to:
 obtain a priority of the synchronization reference, SyncRef, UE ( 208 ,  210 ,  212 ,  214 ,  502 ); include the SLSS ID of the synchronization reference, SyncRef, UE ( 208 ,  210 ,  212 ,  214 ,  502 ) in the set of SLSS IDs when the priority of the synchronization reference, SyncRef, UE ( 208 ,  210 ,  212 ,  214 ,  502 ) is higher than or equal to the priority of the UE ( 102 ). 
 
     
     
         7 . The UE ( 102 ) according to  claim 1 , wherein the transceiver ( 104 ) is enabled for beamforming wherein the first signal is received on a first beam, and the processor ( 106 ) is further configured to operating the power level for transmitting synchronization signal on the first beam. 
     
     
         8 . The UE ( 102 ) according to  claim 1 , wherein the first synchronization source ( 108 ) is a Base Station, BS, ( 202 ) and wherein the processor ( 106 ) is further configured to operate the power control based on a DownLink PathLoss, DL PL, of the first signal. 
     
     
         9 . The UE ( 102 ) according to  claim 1 , wherein the first synchronization source ( 108 ) is a synchronization reference, SyncRef, user equipment, UE, ( 208 ,  210 ,  212 ,  214 ,  502 ) and wherein the processor ( 106 ) is further configured to operate the power control based on a Reference Signal Received Power (RSRP) of the first signal. 
     
     
         10 . The UE ( 102 ) according to  claim 9 , wherein the processor ( 106 ) is further configured to:
 compare the Reference Signal Received Power (RSRP) of the first signal with a threshold value and operate the power control based on the comparison.   
     
     
         11 . The UE ( 102 ) according to  claim 1 , wherein the processor ( 106 ) is further configured to:
 determine the power level of a data transmission and operate the power control based on the power level of the data transmission when the UE ( 102 ) is transmitting data.   
     
     
         12 . The UE ( 102 ) according to  claim 11 , wherein the processor ( 106 ) is further configured to:
 operate the power control based on the power level of the data transmission and a pre-specified offset value.   
     
     
         13 . The UE ( 102 ) according to  claim 1 , wherein the first signal is received from the first synchronization source ( 108 ) having a first sidelink synchronization signal, SLSS, identifier, ID, and the processor ( 106 ) is configured to operate power control of transmission of a synchronization signal based on the first signal and the set of the set of SLSS IDs by determining when the first SLSS ID is within the set of SLSS IDs. 
     
     
         14 . The UE ( 102 ) according to  claim 1 , wherein the UE ( 102 ) is arranged for acting as a Synchronization Reference UE (SyncRef UE) ( 206 ) in a sidelink communication network. 
     
     
         15 . A method ( 100 B,  400 ) for operating sidelink communication in a User Equipment, UE, ( 102 ) wherein the method ( 100 B,  400 ) comprises receiving a first signal from a first synchronization source ( 108 ), obtaining a set of sidelink synchronization signal, SLSS, identifiers, IDs; operating power control of transmission of a synchronization signal based on the first signal and the set of SLSS IDs.